A. Field of the Disclosure
The present disclosure relates generally to compositions of oxygenated hydrocarbon compounds. Such compositions as well as methods for making the same are disclosed.
B. Background
Fuel oxygenates (also known simply as “oxygenates”) are oxygen compounds that are added to fuels, especially gasoline, to make them burn more efficiently. Adding oxygenates to gasoline boosts the gasoline's octane level and reduces atmospheric pollution associated with fuel combustion. Commonly used fuel oxygenates are organic compounds with oxygen-containing groups, specifically hydroxyl groups and ether groups. Examples of commonly used fuel oxygenates are methyl tert-butyl ether (MTBE), tert-amyl methyl ether (TAME), diisopropyl ether (DIPE), ethyl tert-butyl ether (ETBE), tert-amyl alcohol (TAA), tert-butyl alcohol (TBA), and ethanol.
By increasing the oxygen content of the fuel, the oxygenate causes the fuel to burn more completely, creating a higher yield of carbon dioxide and lower amounts of noxious pollutants such as carbon monoxide and hydrocarbons. This is environmentally beneficial, as carbon monoxide and volatile hydrocarbons are toxic to humans, animals, and plants. Both types of compounds are directly toxic to organisms upon direct expose and are indirectly toxic due to their ability to generate tropospheric ozone. However, except for ethanol, all commonly used oxygenates are manufactured from fossil hydrocarbons such as petroleum products and natural gas products. Burning oxygenates from fossil hydrocarbons poses the same environmental threat that is posed by the burning of all fossil hydrocarbons: it causes a net increase in atmospheric carbon dioxide, which in turn increases anthropogenic global warming. There is currently a strongly felt but unmet need for fuel components such as oxygenates from sources other than fossil hydrocarbons that will not contribute to a net increase in atmospheric carbon dioxide.
There is also a long-felt but unmet need for oxygenates that can be produced in countries without large fossil fuel reserves. The commonly used oxygenates are produced at least partially from reagents that are in turn obtained from petroleum and natural gas. For example, MTBE is produced by reacting methanol (obtained from natural gas) and isobutylene (obtained from petroleum or natural gas). ETBE is produced from isobutylene and ethanol; ethanol is generally produced from biological sources, so that the burning of ETBE produces less net-carbon emissions. Countries without access to large fossil fuel reserves are forced to import fossil fuels or fossil fuel derivatives as a raw material for the production of oxygenates. This has negative economic effects on the importer, and in some cases dependence on foreign fossil fuels can undermine the importer's national security.